Cleaning of oil stills and removal of coke from them at a refinery in the United States.

An oil refinery in the United States. When oil has passed from stills after distillation, there remains coke which must be removed. A man wears a mask and gloves before entering a still. The man removes coke from the still. Workmen relax. Coke is cooled. Workers shovel coke. A crane dumps coke. Oil is transported to stills where test products are made by further distilling. A receiving house where pumps are used to pump oil to the stills and from the stills back to the receiving house.